At cold start-up of a hydrocarbon fuel powered internal combustion engine, fuel combustion typically is incomplete, resulting in significant and undesirable amounts of unburned hydrocarbons in the engine exhaust. Further, these residual hydrocarbons are incompletely oxidized by an exhaust gas catalytic converter which is also cold, such that a cold-starting engine typically emits significant amounts of unburned hydrocarbons to the atmosphere. This situation continues to pertain until the engine and the converter reach their respective intended operating temperatures.
What is needed in the art is a means for starting an internal combustion engine and fueling it while producing an engine exhaust containing significantly reduced amounts of unburned hydrocarbons.
It is a principal object of the present invention to provide an internal combustion engine exhaust having substantially reduced amounts of unburned hydrocarbons under all conditions of engine operation.
It is a further object of the invention to provide a system for fueling an engine whereby steady-state hydrocarbon fuel, such as raw gasoline or diesel fuel, is withheld until engine operating conditions permit complete combustion of the steady-state fuel.